1. Technical Field
This invention relates to venting devices that are used to provide air circulation through hollow block and like wall construction. Such walls are below grade and are prone to moisture buildup and associated dampness which can promote the growth of unhealthy airborne mold and mildew.
2. Description of Prior Art
Prior art devices of this type have been relied on a variety of ventilating wall elements and inserts, see U.S. Pat. Nos. 761,711, 2,657,570, 2,931,215, 3,429,084, 4,159,673, 4,656,802, 4,910,937, and 6,912,820. U.S. Pat. No. 761,711 is directed to a ventilating-wall construction in which custom-molded building bricks are provided with interconnected venting passageways when in a wall configuration. Venting portals are provided in some bricks for inlet air flow.
U.S. Pat. No. 2,657,570 discloses rectangular flat sheet wall ventilators that are fitted into the joints between the blocks during construction.
U.S. Pat. No. 2,931,215 claims the combination of tie-down and wall ventilators that comprises a hollow stake that is positioned vertically inside the block wall, extending between adjacent blocks with upstanding retainment tongues engageable on the block surfaces forming an anchor.
U.S. Pat. No. 3,429,084 shows an insect-proof weep hole of a Z-shape conduit with a screened insert therein. The device is positioned in the mortar joint between the blocks allowing for moisture transfer from behind the wall.
U.S. Pat. No. 4,159,673 discloses a vent block having a plurality of adjacent vent holes with an air duct in communication therewith respectively.
A vent pipe configuration for block walls can be seen U.S. Pat. No. 4,656,802 having a screened end cap for positioning in the tops of the block wall cavities.
In U.S. Pat. No. 6,912,820 a drainage system for concrete masonry wall construction is disclosed, having a tray unit with a strip of water permeable material attached which provides a water conduit from the interior of the wall.